DEMU trains likely to be back on track

Bangladesh Railway has planned to revive its diesel-electric multiple unit (DEMU) train fleet sitting idle for years due to lack of maintenance and spare parts unavailability.

But this time sophisticated Chinese operating technology will be replaced by conventional ones to simplify operation and ease maintenance. A team of railway engineers has already finished work on a unit making it functional.

After a total of 30 trial runs and latest six to seven up-to-the-mark outcome, they have decided to run the unit on a shorter distance on the Parbatipur-Rangpur route from the first week of September.

In 2013 Bangladesh Railway purchased 20 sets of DEMU trains from China but most of them went out of service within seven years ruining a Tk598.84 crore project miserably.

As the trains have gathered dust for years, the railway wanted to be back to the service but the Chinese suppliers wanted huge amount of money to provide parts and technical support.

The railway then tried to do the repair work by its own technology and engineers.  

They removed original Chinese technology, which is complicated and costly, and replaced it with conventional one which is more affordable and engineers have capacity of maintenance, officials said.

Railway will call tender for the rest of the units later if all goes well, they said.

Md Monjur-ul-Alam Chowdhury, Additional Director General of Bangladesh Railway, has recently told the media that the expensive DEMU trains have long shelf life but technical failure has made them unusable.   

The Railway wanted the Chinese train supplier to repair them. But the cost they estimated was almost the same as the purchase price, which was impossible for railway to bear, he said.  

“Then we took an attempt to repair them from scratch,” he told a news outlet.

Md Asaduzzaman, Chief Executive of Central Locomotive Workshop, Parbatipur, told The Business Post that they would hand over the first unit for commercial operation before September.

“We will hold another final trial and then pass it to ply on a regular route. This commercial operation is, however, also a part of a sustainability test,” he added.

This set of DEMU will run for two months with passengers. If all goes well, works on the rest of the trains will be started. “The first one is a test case. We will try to maximize passenger carrying capacity for the next ones,” added.

DEMU’s technology replaced

A five-member team formed by the railway worked for one and a half years in collaboration with Buet experts on mechanical and electronic issues.  

Bangladesh Atomic Energy Commission’s former official Md Asaduzzaman, one of the team members, said all trains of the railway run by DC motors while DEMU runs by AC motors, the first of its kind in Bangladesh. It is sophisticated and highly costly.

These are fully electrical. As Bangladesh Railway doesn’t have electrical engineers it is tough for them to do maintenance works after the Chinese Company’s after sale service contract ended.

“So we changed the system including the generator and motors to conventional one,” he said.

The automated DEMU has communication modules that need software programing. This system needs to be upgraded and maintained. “We just removed them and placed an analog system,” he said.

For example, temperature, speed and fuel gauge - all are now displayed on analog display boards, he said.

 DEMUs have sophisticated parts. “We have built a system that now can be replaced by available ones in the local market. We have replaced inverter, generator etc. This will reduce maintenance cost drastically,” he said.

He hoped that the costs of the repair of other units will be reduced further. “We did an experiment while replacing parts - some did not match while some others damaged and burnt. Now we know which ones will fit,” he said.

The railway technical team will work on other units gradually. They will examine them to find out what kinds of parts and repairs they need and work accordingly.

“We will then make a case-to-case estimate after examining the real condition of the units and ask for a budget,” he told The Business Post.

According to the railway, each DEMU train can carry 300 passengers. During trial the repaired unit carried a load of 720 passengers. The train ran at a speed of 60-70 kilometers per hour. 

Md Asaduzzaman said they would also bring changes in the ventilation system of the trains manually. “These did not have air conditioning but the windows were too small to take air in. So, we cut the roof and installed a ventilator for air circulation.”

The technical team told the railway that a dedicated engineering workshop should be introduced for these trains in future. However, for now, the existing workshops can do it well if some fine tuning is made.

All trains in service in Bangladesh have engines above the floor level of workshops but DEMU’s engines are below the level. “So, while working on this, engines need to be lifted a bit. This mechanism can be arranged at a low cost,” he said.    

The lifespan of imported Chinese-made trains was 35 years but no significant initiatives were taken for the maintenance of the trains as they started to malfunction within years.

In 2017, the government’s project evaluation agency - Implementation, Monitoring and Evaluation Division (IMED), in a report said the railway did not hire additional workforce for the maintenance and set up no dedicated workshop as well.

DEMU’s parts also did not match with trains of the existing fleet, it said.

These trains were operated on eleven routes ranging from 22 kilometers to 176 kilometers.